[time-nuts] cheap 5V OCXO in 14DIP has about 1E-9 drift per day

[Greg Broburg]

10.000005 = 26 - 15.999995

15.999995 = 26 - 10.000005

This pair of equations is insufficient to define
that the ratio between these two frequencies
is exactly 1.6 : 1 or 1 : 1.6

There must be an additional concept here.

Greg


On 4/9/2011 6:59 PM, Hal Murray wrote:
> bruce.griffiths at xtra.co.nz said:
>> The 16MHz is necessary for the loop to function: The mixer mixes down the
>> 26MHz to a pair of conjugate frequencies, 10MHz  and 16MHz. Thermal and
>> device noise is sufficient to start the process.
>> 10MHz = 26MHz - 16MHz
>> 16MHz = 26MHz - 10MHz
> What makes it stable at 10 and 16 MHz rather than 10.000001 and 15.999999?
>
> I'm assuming we are starting with a good 26 MHz crystal and that it would be hard to get filters that good.
>
>